Forged documents could be signed off for good with a new technique that produces a 3D hologram of handwriting. Through virtual reality and image processing, tiny pressure bumps in writing can be analysed to spot fakes.

Conventional techniques have involved using 2D analyses to examine the sequence of pen strokes. The 3D method could be a "powerful tool" for forensic experts, said the physicists, whose findings are reported in an Institute of Physics journal. Called 3D micro-profilometry, the technology could provide a solution for cracking down on will, cheque, and credit card counterfeiters, as well as the forgers of other important handwritten documents.

We believe this type of 3D micro-profilometry is one of the most promising ways of detecting forged handwriting," said Professor Schirripa Spagnolo, head of the research team at UniversitÃ degli Studi Roma Tre in Rome, Italy.